1.	Nature of the Business and Basis of Presentation

Seres Therapeutics, Inc. (the “Company”) was incorporated under the laws of the State of Delaware in October 2010 under the name Newco LS21, Inc. In October 2011, the company changed its name to Seres Health, Inc., and in May 2015, the Company changed its name to Seres Therapeutics, Inc. The Company is a microbiome therapeutics platform company developing a novel class of biological drugs, which are designed to restore health by repairing the function of a dysbiotic microbiome. The Company’s lead product candidate, SER-109, is designed to prevent further recurrences of Clostridium difficile infection (“CDI”), a debilitating infection of the colon, and, if approved by the U.S. Food and Drug Administration (“FDA”), could be a first-in-field drug. Using its microbiome therapeutics platform, the Company is developing additional product candidates, including SER-262 to prevent an initial recurrence of primary CDI and SER-287 to treat ulcerative colitis, and other product candidates to treat enteric pathogens, such as antibiotic-resistant bacteria. The Company is also conducting research on metabolic diseases, such as early-stage, non-insulin dependent diabetes; other inflammatory diseases, such as Crohn’s disease; and infections related to antibiotic use, cancer chemotherapy and immune suppression.

The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. Product candidates currently under development will require significant additional research and development efforts, including extensive pre-clinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance-reporting capabilities.

The Company’s product candidates are in development. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees and consultants.

The Company’s consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets and the satisfaction of liabilities in the ordinary course of business. The Company has experienced negative cash flows and had an accumulated deficit of $82,612 and $27,832 as of December 31, 2015 and 2014, respectively. The Company expects that its cash, cash equivalents and investments at December 31, 2015 of $205,082 will enable it to fund its operating expense and capital expenditure requirements through at least December 31, 2016. The future viability of the Company is dependent on its ability to generate cash from operating activities or to raise additional capital to finance its operations. The Company’s failure to raise capital as and when needed could have a negative impact on its financial condition and ability to pursue its business strategies.

On July 1, 2015, the Company completed an initial public offering (“IPO”) of its common stock, and issued and sold 8,545,138 shares of common stock at a price to the public of $18.00 per share, resulting in net proceeds of approximately $139,267 after deducting underwriting discounts and commissions and offering expenses. The shares issued upon closing of the IPO included 1,114,583 shares of the Company’s common stock, which were sold to the underwriters pursuant to the full exercise of their option to purchase additional shares of common stock. Upon the listing of the Company’s common stock on the NASDAQ Global Select Market (“NASDAQ”) on June 26, 2015, all outstanding shares of the Company’s convertible preferred stock automatically converted into 22,866,987 shares of the Company’s common stock. In addition, at this time, the warrant to purchase shares of the Company’s Series A-2 convertible preferred stock was converted into a warrant to purchase shares of the Company’s common stock.

The accompanying financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts of the Company and its wholly owned subsidiaries after elimination of all intercompany accounts and transactions.